All-polarization-maintaining, efficiently wavelength-tunable, Er-doped mode-locked fiber laser with a compact reflective Lyot filter

Abstract

Wavelength tunable mode-locked fiber lasers have highly potential applications in precision spectroscopy, nonlinear microscopy and photonic sensing. Here, we present a compact and thermal-sensitive reflective Lyot filter and utilize it for all-polarization-maintaining efficiently wavelength-tunable Er-doped carbon-nanotube-mode-locked laser for the first time, to the best of our knowledge. The output wavelength of the laser can be tuned from 1544.46 nm to 1572.71 nm, with a wide tuning range of 28.25 nm, and a remarkable tuning efficiency of 0.589 nm/°C, when the angle-spliced fiber is only 8.2 cm and the free spectral range of the filter is 31.32 nm. Dual-wavelength mode-locking is also achieved at boundary temperatures when increasing the pump power. Due to its compact size and reflection configuration, the proposed reflective Lyot filter is promising for realizing highly efficient wavelength tuning and multiwavelength generation in all-polarization-maintaining fiber lasers where reflective filters are needed.

C- and L-Bands Wavelength-Tunable Mode-Locked Fiber Laser

“…As the tuning characteristics of a laser depend largely on the tunable filter, much effort has been put into building filters with excellent performance to expand the tunable fiber laser. So far, various filtering techniques have been explored, including Lyot filters [20,21], reflection gratings [22,23], fiber optic gratings [24], Sagnac loop filters [11,[25][26][27][28], volume Bragg gratings [29], and intracavity birefringence filtering effects [30,31], etc. Nyushkov B. et al achieved tuning of the output radiation wavelength from 1524 nm to 1602 nm over a range of 78 nm using a reflection diffraction grating [22].…”